A new law signed by Gov. Jerry Brown over the weekend will impact some Orange County cities that for years have forced businesses they contract with to use a federal system intended to weed out people working in the country illegally.

Touted as a way to unburden employees and help job growth, AB1236 prohibits the state, cities, counties and special districts from requiring employers to use E-Verify, a free Internet-based system that checks if a job applicant is allowed to legally work in the country.

This means that some cities in Orange County, such as Orange, Mission Viejo, San Juan Capistrano, Yorba Linda and Placentia, will probably have to do away with clauses in some of their city contracts that require employers they do business with to use the federal tool.

City officials said Wednesday they would revisit the issue and most probably comply with the new law set to go into effect Jan. 1. Some expressed disappointment.

â€œI wish the state of California would just take care of their own business and leave local governments to do what we do,â€ Orange Mayor Carolyn Cavecche said.

The only exception to the state law is when required by federal law or for those who contract with the federal government.

While California does away with mandatory E-Verify, a bill that would mandate every employer use the system may soon be taken up by Congress. The bill cleared a congressional committee in September, but it’s unclear whether House Speaker John Boehner, a Republican, will allow the bill to reach a vote.

The E-Verify system compares information from an employee’s I-9 employment form with Social Security Administration and Department of Homeland Security records.

Orange city officials said they’ll still try to ensure that employers who contract with them will only hire legal workers.

If the city can’t mandate the use of E-Verify, they’ll figure another method, Cavecche said.

Orange City Attorney David Deberry said only some of the employers they contract with were forced to use the federal system. Several of their landscape contractors and others who do work on city grounds, parkways and parks fell into that category.

The city requires those employers to ensure that each of their employees not only clears E-Verify but also has a valid driver’s license and Social Security number.

Ultimately, Deberry said, he doesn’t believe doing away with mandatory E-Verify is going to matter much except for a very limited number of employees who may have an I-9 form and driver’s license that are fake and E-Verify would catch.

â€œPotentially, some employees will slip through the cracks,â€ Deberry said. â€œIt’s a possibility that some people who are not legally entitled to do work will be working on city contracts.â€

There were a few times when E-Verify found illegal workers slated to work on city contracts, he added.

City officials in San Clemente, which also mandates some employers they contract with to use E-Verify, did not return a call for comment.

Supporters of the bill, including its creator Assemblyman Paul Fong, D-Cupertino, say mandating the program puts an unnecessary burden on businesses that are already suffering during the recession.

Proponents also say the system is not sufficiently up to date to meet requirements for accurate verification, keeping employers from hiring employees in a timely manner and keeping workers from earning wages.

Mission Viejo Councilwoman Patricia Kelley, a longtime supporter of E-Verify in her city, said she understands the concerns about burdens on businesses.

However, the mandate was a good thing for her city, she said.

â€œAs a city, we kind of stuck our neck out and were one of the first in Orange County to adopt the program,â€ she said. â€œI think it made a difference not only in our community but Orange County.â€

Kelley said many of the businesses they contracted with would have used the system anyway and will continue to do so.

Opponents of the new bill, such as NumbersUSA.com, say mandatory E-Verify is good for the state because it pushes illegal immigrants from the workforce, leaving jobs open for Californians who are legal residents or U.S. citizens.

San Juan Capistrano Councilman Derek Reeve was the only official who mentioned the possibility of challenging the law.

â€œI would like to receive a legal opinion as to whether the city has grounds to challenge this law and if so join forces with other cities with similar laws,â€ he said in a written statement.

Reeve said the passing of this bill and others â€“ the California DREAM Act and a measure that outlaws the practice of seizing cars of sober, unlicensed drivers â€“ â€œtruly declares California as an amnesty state at the expense of US Citizens and lawful residents.â€

He had pushed a proposal to prohibit employers in the city from hiring people who are in the country illegally and allow the city to act on violations. However, in late September, he put the measure on hold to see how this bill and federal legislation would play out.